996 resultados para Reciprocity and Ritual. Homer and Tragedy in the Developing City-State
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Several anomalies occur in the developing neural and visceral head skeleton of young specimens of Neoceratodus forsteri that have been reared under laboratory conditions. These include anomalies of the basicranium and its derivatives, aberrations of the anterior mandible and hyoid apparatus, and abnormalities in the articulation of the jaws and the elements that produce them. Apart from the occasional absence of the basihyal, and failure of the quadrate processes to form, the anomalies are not deficiencies. Most involve malformations of parts of the neurocranium and visceral skeleton, inappropriate articulations or fusions between elements, disunity in structures that are normally fused and the appearance of supernumerary elements. The incidence of chondral anomalies, generally higher than aberrations that occur in the dermal skeleton in juvenile lungfish, ranges from 1-10% in laboratory reared individuals that have not been subjected to experimental interference. The anomalies differ from those found in many amphibian populations, in the field and in the laboratory, because they involve the cranium, and not the limbs, and the lungfish have not been exposed to the factors that cause anomalies in the amphibians. It is unlikely that the existence of those anomalies, if it is reflected in the wild population, places a selective pressure on the lungfish, because, in a normal season, less than 1% of the total number of eggs produced survive to be recruited into the adult population.
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The effect of heating and cooling on heart rate in the estuarine crocodile Crocodylus porosus was studied in response to different heat transfer mechanisms and heat loads. Three heating treatments were investigated. C. porosus were: (1) exposed to a radiant heat source under dry conditions; (2) heated via radiant energy while half-submerged in flowing water at 23degreesC and (3) heated via convective transfer by increasing water temperature from 23degreesC to 35degreesC. Cooling was achieved in all treatments by removing the heat source and with C. porosus half-submerged in flowing water at 23degreesC. In all treatments, the heart rate of C. porosus increased markedly in response to heating and decreased rapidly with the removal of the heat source. Heart rate during heating was significantly faster than during cooling at any given body temperature, i.e. there was a significant heart rate hysteresis. There were two identifiable responses to heating and cooling. During the initial stages of applying or removing the heat source, there was a dramatic increase or decrease in heart rate ('rapid response'), respectively, indicating a possible cardiac reflex. This rapid change in heart rate with only a small change or no change in body temperature (
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Early pregnancy factor (EPF) is a secreted protein with immunosuppressive and growth factor properties that has been shown to suppress acute experimental autoimmune encephalomyelitis (EAE) induced with myelin basic protein (MBP) in Lewis rats. EAE is associated with infiltration of the central nervous system (CNS) with inflammatory cells. Spontaneous recovery involves the loss of T lymphocytes from the CNS and the selective apoptosis of Vbeta8.2(+) cells. In the present study, T cell, macrophage (CD11b/c(+)) and B cell (CD45RA(+)) populations in spinal cord and popliteal lymph nodes (LN) of Lewis rats with EAE were quantitated and apoptosis was studied. Rats were treated with EPF or vehicle. Following treatment on day 14 after inoculation with MBP, neither 1 x 100 mug nor 2 x 100 mug doses of EPF affected the total number of cells infiltrating the spinal cord on day 15, although the higher dose caused a decrease in the number of CD5(+) and CD11b/c(+) cells. Treatment with 2 x 100 mug/day from days 10 to 14 decreased the total number of infiltrating cells, and the numbers of CD5(+), CD11b/c(+) and CD45RA(+) cells. Apoptosis was unaffected. No alteration on the number or type of inflammatory cells in the popliteal LN was observed after treatment on days 10-14. However, treatment with EPF from days 0 to 11 increased the total number of T and B cells and CD5(+) T cells found on day 12 in the LN. Similarly, there was an increase in the frequency of MBP-reactive cells in the LN as determined by limiting dilution analysis. These results suggest that EPF treatment reduces the numbers of lymphocytes and macrophages in the CNS, possibly through an effect on cell trafficking. (C) 2003 Elsevier B.V. All rights reserved.
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The use of thermodilution and other methods of monitoring in dogs during surgery and critical care was evaluated. Six Greyhounds were anaesthetised and then instrumented by placing a thermodilution catheter into the pulmonary artery via the jugular vein. A catheter in the dorsal pedal artery also permitted direct measurement of arterial pressures. Core body temperature (degreesC) and central venous pressure (mmHg) were measured, while cardiac output (mL/min/kg) and mean arterial pressure (mmHg) were calculated. A mid-line surgical incision was performed and the physiological parameters were monitored for a total of two hours. All physiological parameters generally declined, although significant increases (P<0.05) were noted for cardiac output following surgical incision. Central venous pressure was maintained at approximately 0mmHg by controlling an infusion of sterile saline. Core body temperature decreased from 37.1+/-0.6degreesC (once instrumented) to 36.6+/-0.60degreesC (at the end of the study), despite warming using heating pads. Physiological parameters indicative of patient viability will generally decline during surgery without intervention. This study describes an approach that can be undertaken in veterinary hospitals to accurately monitor vital signs in surgical and critical care patients.
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In the post-Cold War world, Africa has been an important focus of Brazilian foreign policy. Having a significant historical weight in building our nation, African countries are also part of the moves adopted by Brazil's foreign policy. The main purpose of the present text is to show this relevant regional dimension regarding Brazil's international insertion during the Lula era. The work is divided in two parts: the first part approaches Africa's international insertion throughout recent years and the second analyses the dimension occupied by African affairs in Brazil during the Lula era. The main argument is that the new role played by Africa in the international scene coincides with a global Brazil
Chinese energy policy progress and challenges in the transition to low carbon development, 2006-2013
Resumo:
If the world is not to jeopardize the chances for human life on Earth, climate change must be mitigated; therefore, achieving low carbon development is crucial. China is the world's greatest GHG emitter, energy producer and energy consumer; investigating its energy-climate policy developments and international positions are of utmost importance to understand and tackle current stumbling blocks of the global energy and climate governance.
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This article presents the results of a research to understand the conditions of interaction between work and three specific information systems (ISs) used in the Brazilian banking sector. We sought to understand how systems are redesigned in work practices, and how work is modified by the insertion of new systems. Data gathering included 46 semi-structured interviews, together with an analysis of system-related documents. We tried to identify what is behind the practices that modify the ISs and work. The data analysis revealed an operating structure: a combination of different practices ensuring that the interaction between agents and systems will take place. We discovered a structure of reciprocal conversion caused by the increased technical skills of the agent and the humanization of the systems. It is through ongoing adjustment between work and ISs that technology is tailored to the context and people become more prepared to handle with technology.
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Revista Lusófona de Línguas, Culturas e Tradução